An unannounced fireworks show over downtown Ottawa surprised and confused many people late Thursday night. A councillor for the area said the decision was made by the city and federal government.

CBC News and several city councillors received complaints about unexpected fireworks in the LeBreton Flats area late Thursday night.

While the Ottawa Bluesfest music festival, which began Thursday at LeBreton Flats, occasionally includes fireworks for headline sets, Thursday’s fireworks went beyond the festival’s 11 p.m. ending — and the start of the city’s overnight noise limit.

“On a week night, so late, with no notice [is] unacceptable,” Somerset ward Coun. Ariel Troster said on Facebook.

Kitchissippi Coun. Jeff Leiper said the city told him the fireworks were meant to be set off for the national Canada Day show which, along with other national events, were cancelled by major afternoon thunderstorms that brought flash floods and power outages.

“It was deemed by Canadian Heritage that it was safer to dispose of them that way rather than dismantle and move them, so they took this step in conjunction with Bluesfest,” he said.

CBC News and Radio-Canada have asked Canadian Heritage for comment and have not yet heard back.

The city said its team handling special events decided not to tell people about the fireworks show to avoid a large number of people gathering outside of a major music festival, creating an “event surrounding an event.”

“After considering the available options, [the team] determined that the public safety risks associated with encouraging additional attendance in the surrounding area outweighed the benefits of broader notification,” said Ryan Perrault, Ottawa’s emergency and protective services general manager.

Leiper was angry at the decision and fundamentally disagreed with it, he wrote online.

“A no-notice fireworks show of this scale is completely inappropriate and legitimately frightened Ottawa residents,” he wrote.

The city told Bluesfest not to advise the public the fireworks would happen, a festival spokesperson told CBC News.

The fireworks lasted roughly 11 to 12 minutes from about 10:53 p.m., the city said, and as of Friday morning it had received nearly 40 complaints.

“City staff will consider feedback received as part of the post-event debrief process to ensure any lessons learned are incorporated into future planning,” the city’s Perrault said.